For this gig, I used two cameras (E-5 and E-M5) with a few different lenses, but most of the stuff backstage (and at least half of the keepers) is shot with the Voigtländer 17.5mm F0.95 Nokton. In fact it was the maiden trip for this lens that I had just acquired. Wanting to use ONLY natural light, really fast apertures were a necessity in the very dimly lit backstage area. And the focal length was perfect for documentary.

Some samples (but you can see many more, much bigger, and in proper context, in the gallery):